Virtualization is a technique used to support independent execution environments on a single computer. An execution environment is typically used to execute one or more applications under a guest operating system that is independent of other execution environments running on the same computer. Each execution environment can be configured as a guest partition, otherwise known as a virtual machine. The guest partition is a software implementation of a computer that executes applications as if they were executed on a single computer. The guest partition is configured by a hypervisor that also manages the allocation of resources for the guest partition.
The hypervisor operates in an execution environment that is separate from the guest partition and has no knowledge of the health of the applications running in the guest partition. As such, anomalous events that occur within an application can only be remedied by the application or the guest operating system. However, if the application or the guest operating system cannot remedy the anomalous event, the application may suffer a catastrophic failure.